An image forming apparatus includes a fixing device. The fixing device fixes a toner on a sheet through heat fixing. As the fixing device, a belt fixing device and a roller fixing device are known.
The belt fixing device includes a roller and a belt. In the belt fixing device, a fixation nip is formed by the roller and the belt abutting onto each other.
The roller fixing device includes a pair of rollers. In the roller fixing device, a fixation nip is formed by the pair of rollers abutting onto each other.
The belt fixing device can form a fixation nip that has a wider nip width than a fixation nip formed by the roller fixing device.
However, when the nip width is large, there is a problem that a wrinkle is likely to be generated on a sheet.